#include <REGX52.H>

void Delay(unsigned int xms)	//@12.000MHz
{
	unsigned char data i, j;
	while(xms--)
	{
		i = 2;
		j = 239;
		do
		{
				while (--j);
		} while (--i);
	}
	
}

void main()
{
	unsigned char LEDNum=0;
	while(1)
	{
		if(P3_1==0)
		{
			Delay(20);
			while(P3_1==0)
				Delay(20);
			LEDNum++;
//			0000 0000
//			0000 0001
//			1111 1110
			P2=~LEDNum;
		}
	}
}